Generally speaking, regenerative air systems are more environmentally friendly than are vacuum or mechanical broom sweepers. There are several factors that contribute to this.

Regenerative air sweepers employ a closed loop, 'cyclonic effect', to clean. They are similar to vacuum sweepers, in that there is a similar vacuum inlet located on one side of the sweeping head. Unlike vacuum machines, however, regenerative air sweepers constantly re-circulate (regenerate) their air supply internally. To accomplish this, the re-circulating air is blasted into the sweeping head on the side opposite the pickup, or inlet, tube.Essentially, the air 'blasts' down onto the pavement on one side of the head, travels across the width of the head (gathering debris with it as it goes), and then travels up the pickup hose on the other side with the debris. Manufacturers design their sweeping heads so as to swirl the air, so it will retain the collected debris within the airstream as it moves from the blast to the intake side of the head.Like any other sweeper type, regenerative air machines can be equipped with gutter brooms to brush material accumulated against the curb into the path of the sweeper. Regenerative air models, like any other type of sweeper designed to clean the entire lane, can be equipped with gutter brooms on both sides of the machine. This affords the operator the opportunity to effectively sweep both sides of a one-way street without creating a traffic hazard.Because of the way they operate, regenerative air sweepers are recognized as providing a more thorough cleaning action 鈥? even though a vacuum system may be able to boast a greater airflow per horsepower. Because they 'air-blast' the pavement across the entire width of the sweeping head, regenerative air sweepers tend to do a better job of cleaning over the entire pavement surface covered and are recognized for this capability.Although some air is lost by the regeneration process (due to unevenness of the pavement, which allows air to escape from under the sweeping head's rubber flaps, etc.), the amount of exhausted, pollutant-laden air is typically much less than with a vacuum sweeper. Because of this, and the fact that regenerative-based machines also tend to pick up the small micron particles across the entire sweeping head, regenerative air sweepers are usually a better choice where either air quality or storm water runoff pollution are concerns.All standard regenerative air sweepers (excluding high-efficiency models discussed in the next section) have the means to introduce water into the vacuum intake on the curb side to help knock down the dust in the hopper. Plus, many believe the blast-and-pickup cycle of these machines also makes them more capable at picking up heavy debris, since the blast is more able to dislodge heavier materials and get them into the airflow. Due to fewer moving parts, none of which touch the pavement, a regenerative air machine is less expensive to maintain that the mechanical brush sweeper.The blast-and-pickup cycle also makes these machines more capable at picking up heavy debris, since the blast is more able to dislodge heavier materials and get them into the airflow. However, it should be noted that some vacuum sweepers have been able to remove concrete chunks up to 8" in size as part of bridge deck reconstruction, for example. Plus pure vacuum machines have been shown to be the best choice in rejuvenating plugged porous pavement and the stronger the airflow the better the results.However, regenerative air sweepers are also able to support larger intake tubes, so larger debris may be removed without clogging. This is especially important when sweeping material such as leaves.Today's air machines, which include regenerative air and vacuum sweepers, are able to supplant mechanical broom sweepers for all but the most challenging applications. Several air machine models are now available with fugitive dust controls and these will be discussed in the next section. In most applications, they also are a better choice than are vacuum sweepers. Some models are now available for use without dust suppression water, as will be discussed in the following section.Regenerative air sweepers are more suitable for most everyday road sweeping needs, and also cost significantly less to maintain. For these reasons, regenerative air sweeping equipment is now often being specified by U.S. governmental agencies that are involved in paying a portion of sweeping equipment being purchased.Advantages:

Best all around, multi-purpose sweeper. Can clean a wide range of debris in a large variety of situations. Work very well under routine street maintenance-type operations, for cities or contractors in their routine cleaning programs. Air system makes them better for leaves than mechanical broom sweepers, and larger intake hoses makes them better than vacuum sweepers for leaves. Fewer moving and wear parts than mechanical sweepers. Can be used to clean catch basins by adding hand hose. The sweeping industry's most multi-purpose machine. Some models are now available for use without dust suppression water.Disadvantages:

Can't handle millings, spring cleanup and other extremely heavy-duty applications as well as can mechanical sweepers. They use water for dust suppression, which leaves some dissolved small-micron debris in pavement cracks and on the surface. They exhaust some amount of particulates into the atmosphere.